Issue Uploading JSON File for Prompt Reference in Azure AI Foundry (415 Unsupported Media Type)

Hello Azure Support,

I am currently developing a project where I want to use AI to summarize reports. The expected workflow is:

1. Upload a JSON file (around 23KB) containing the raw report.

Summarize the report via AI and store the result as JSON.

Run a prompt that references the uploaded file (instead of embedding the JSON directly in the prompt since it is too large).

Here is what I’ve done so far:

I have successfully deployed a model in Azure AI Foundry.

I tested it in the Playground — uploaded a file into a vector store and referenced it in my prompt, and it worked correctly.

I also built a simple application in JavaScript for chat completions, and that worked fine.

The problem arises when I try to upload the JSON file via JavaScript. I consistently get the error:

APIError: 415 Unsupported Media Type

Despite following the documentation here: https://learn.microsoft.com/en-us/azure/ai-foundry/quickstarts/get-started-code?tabs=javascript&pivots=fdp-project

I’ve tried multiple approaches but still encounter this issue when attempting the upload + prompt reference flow.

Could you please clarify the correct way to upload a JSON file via JavaScript and then reference it in a prompt? Any working example or guidance would be highly appreciated.

Thank you,Hello Azure Support,

I am currently developing a project where I want to use AI to summarize reports. The expected workflow is:

Upload a JSON file (around 23KB) containing the raw report.

Summarize the report via AI and store the result as JSON.

Run a prompt that references the uploaded file (instead of embedding the JSON directly in the prompt since it is too large).

Here is what I’ve done so far:

I have successfully deployed a model in Azure AI Foundry.

I tested it in the Playground — uploaded a file into a vector store and referenced it in my prompt, and it worked correctly.

I also built a simple application in JavaScript for chat completions, and that worked fine.

The problem arises when I try to upload the JSON file via JavaScript. I consistently get the error:

APIError:

Despite following the documentation here:
https://learn.microsoft.com/en-us/azure/ai-foundry/quickstarts/get-started-code?tabs=javascript&pivots=fdp-project

I’ve tried multiple approaches but still encounter this issue when attempting the upload + prompt reference flow.

Could you please clarify the correct way to upload a JSON file via JavaScript and then reference it in a prompt? Any working example or guidance would be highly appreciated.

Thank you,
Samuel Benny (Smith Kruz)